Modern imaging techniques, such as single photon emission computed tomography (SPECT) allow the imaging of the interior of a target object without physically penetrating the surface of the target. These techniques are used extensively in the medical field. By allowing indirect observation of the interior of the human body, these imaging techniques give medical professionals increased diagnostic information without the accompanying risk of conventional exploratory techniques.
The scanners used for performing noninvasive imaging tend to be both large and expensive. A typical facility will be able to devote the space and financial resources to install only a limited number of scanning devices. The scanners also tend to be in high demand. For example, at many facilities, the available scanners will be used for both clinical use and research. Accordingly, systems and methods for maximizing the efficient usage of the available scanners are desirable.
The need for non-invasive imaging extends also to the realm of pre-clinical research, where small animals such as mice are often used as experimental models. Such research studies often involve studying the progression of disease and the success or failure of experimental therapies. It is hoped that the animal model closely mimics the human model and that the animal research would accelerate the development of pharmaceuticals and therapies for humans. Just as non-invasive imaging in humans has become valuable for medical care, non-invasive imaging in animals is becoming valuable for pre-clinical research. The ability to image the animal without surgery or dissection means that an animal can be repeatedly imaged to study the progress of disease and therapy.
In order to meaningfully image small animals, the scanner requirements are such that the spatial resolution must be substantially more precise than that for human scanners. Although expensive high-resolution scanners dedicated for imaging small animals is an option, it is desirable that scanners primarily designed for another application or for human use may also be used for this purpose.